The latest innovations in energy tech

ARPA-E is a little known arm of the U.S. Department of Energy that has invested $1.3 billion into new energy technologies since launching in 2010. The projects ARPA-E has backed have also attracted more than $1.25 billion from the private sector.

And ARPA-E is getting a 20% funding boost this year thanks to Mission Innovation, the commitment by President Obama and 19 other world leaders to increase government invest in clean energy.

At a summit last weekin Washington, D.C., funding recipients and other innovators got to show off their inventions and ideas. Here are five of the most interesting projects showcased.